In a phased array radar, in order to change the beam direction, a phase shifter is needed. As one example of this phase shifter, there is a phase shifter of vector composite type having transconductance amplifiers (for example, refer to Nonpatent Literature 1). Each transconductance amplifier has a source-grounded polarity control stage, and an amplification stage located as an upper stage of the polarity control stage. In the phase shifter of vector composite type, an in-phase component (an I signal) and a quadrature-phase component (a Q signal) of an input signal are applied to the amplification stages of separate transconductance amplifiers, and the outputs of the amplification stages are connected to the same load.